
\section{Motivation \& Problem Statement}
\label{sec:Motivation}

\begin{itemize}
\item Obligations semantics are not defined in the XACML policy language.
\item Obligations are state-based policies and their enforcement is related to the platform that handles them: to the best of our knowledge,
only the authors in \cite{DBLP:conf/codaspy/LiCB12} have proposed a model for obligations management in XACML.
\item There has been no previous work on obligations management that proposes to maintain obligations states so that access decisions 
 can be based on evaluation of previous accesses and obligations fulfillment in the system. 
 \item Show interactions between PEP and PDP and highlight the fact that obligations are stateful and user-specific.
 \item Extension
\end{itemize}